As if her opening set at last weekend’s 2013 MTV Video Music Awards wasn’t proof enough, Lady Gaga made sure the world knew she was back on Sunday (September 1) with a fierce album-preview performance to kick off the monthlong iTunes Festival.

Taking the stage at London’s Roundhouse to play her first full live set since a hip injury
 scuttled her Born This Way Ball
 tour in February, Gaga blasted through seven (mostly unheard) tracks from her upcoming ARTPOP album.

The highly anticipated show, streamed all over the globe, was full of surprises, including the debut of “Jewels & Drugs,” a trap-like tune featuring rappers T.I., Too $hort and Twista and Gaga’s first stab at rhyming.

Dressed in a black ninja-style suit complete with black ski mask and a knife with “Hollywood” written on it, Gaga opened with the thumping new tune “Aura,” singing while strapped into a black cage suspended above the stage. The industrial-style song featured the chorus, “Do you want to see me naked lover?/ Do you want to peek underneath the covers?/ Do you want to see the girl that lives behind the aura?”

Showing no signs of rust, Gaga leisurely changed into sparkly boots and a bra and told her Monsters, “To say that I’ve missed you, it’s a bit of an understatement, isn’t it?” In fact, she said she couldn’t live without them. The next new one, “MANiCURE,” found Gaga in a hand-clap-happy 50s rock mood that folded in a girl group groove and a touch of Joan Jett pop angst amid the repeated plea, “Save me, because I’m addicted to love.” Like a number of the new songs, it went through a variety of seemingly contradictory styles, ending with an extended metal solo coda.

As if her VMA opener didn’t tip Gaga’s hand, it also became clear early on that onstage costume changes are the parlor trick of choice this time around. After getting her “CURE,” as promised, seapunk Gaga
 emerged in a diamond-encrusted shell-kini and giant mussed blonde wig, all applied in a makeup chair plopped into a mock center stage dressing room.

The album’s trip-hoppy title track was heard live for the first time also, complete with the sure-to-be new Monster Nation credo, “My ARTPOP could mean anything … We could belong together/ARTPOP/ARTPOP/ARTPOP!” Because she’s Gaga, when a Little Monster threw a plaid shirt on stage, Gaga slipped it on over the bikini, along with her own sky-high heeled black boots. (They also tossed up any manner of little pigs, in honor of her many #Swinefest tweets in the days leading up the show.)

Hours before the show started, Gaga tweeted her excitement about the ARTPOP reveals, writing, “I can’t believe it’s finally here! Tonight I premiere/perform 7 new songs from ARTPOP! On a scale of 1 to 10 how excited are you? Monsters?

Because of a reported visa problem, T.I. had to do his verse on the skittering goth-hop “Jewels & Drugs,” via videotape, but that didn’t stop Gaga from dipping into her previously unheard rap diva mode, bouncing around to the beat and sing/rapping the song’s lyrics about the street game. And she wasn’t kidding about having Bay Area rap legend Too $hort
 in the Haus of Gaga this time around, as he rolled out to drop his R-rated verses on the tune, which also featured live rhymes from speed rapper Twista.

The surprise clearly did its work on fans, including one, Ciarán Weir, who wrote shortly after, “Tweeting from the grave because @ladygaga just killed me. #GagaJewelsAndDrugs.”

The fresh tracks kept coming with the theatrical, throbbing pop of “Sex Dreams.” During the latter Gaga channeled Prince, Madonna and anyone else who writhed on, humped or thrusted into a stage in the 1980s while sharing their most intimate, detailed nighttime desires. Stripping off her wig and explaining that ARTPOP was a chance to take off the hair pieces and come out from behind all the disguises, Gaga encouraged her fans to do the same. “I knew I had to show you what’s underneath all of the theater,” said the singer, a brunette, apparently.

On came the sparkly pig nose mask for the industrial dance pop of “Swine,”
 which had Gaga bashing away on a drum kit and using her punk growl and squeal. Her dancers, meanwhile, dressed in smoking snout pig gasmasks, crawled on and flew above the stage in a scene that would make a Cirque du Soleil director wonder just what was going on.

The final freshie was dedicated to the fans Gaga left wanting when she had to abandon her tour. “I don’t wanna grow up/But when the lights come on/You lift me up and I feel strong,” Gaga crooned all alone at a keyboard. “I’d rather be poor and happy than rich and alone … I’ll keep on singin for a living/But I want to be in love/And I wanna be with you,” she sang, appearing to get a bit emotional at points during the power ballad that was both blatantly pandering and touchingly sweet at the same time.

Employing the Green jacket and top hat from the video, Gaga capped the hour-long show with high-energy new single, “Applause,” which ended with a shower of confetti and thousands of hands clapping in the air in unison. We’ll have to wait until November 11 to hear the rest of ARTPOP, but Sunday show’s was ample proof that the Gaga we know and love is back and in full effect.